Your zero-corrosion defense solution for maritime environments

Even sans a buttstock, the amphibian can still be accurately fired by pressing the padded buffer tube against your cheek.

The Amphibian comes shipped in a Nanuk 945 fully waterproof hard case, with a custom -cut foam insert for the pistol and the six included Magpul 30-round pmags.

If you’re looking for the perfect anti-piracy weapon, we have just what you need: the new X7 Fusion Amphibian AR Pistol from Kaiser US Shooting Products. The direct-gas-impingement Amphibian is designed to be completely corrosion proof and 100% reliable in saltwater environments.

Kaiser US Shooting Products is a leading manufacturer of polymer AR upper and lower receivers, and supplies these critical components to ROBAR for their custom-built POLYMAR15 rifles. Kaiser’s composite receivers are injection molded from specially formulated, virgin polymers with impact modifiers and both long- and short-strand glass fibers for the ultimate in impact and shatter resistance. The company has tested their composite receivers through more than 50,000 rounds, with minimal wear and no failures attributable to the receivers, and they stand behind them with a limited lifetime warranty.

Up front the 10.5-inch stainless barrel is topped with a KSP flash can brake—both of which are NP3 coated. A Keymod forend and Magpul AFG grip are standard.

The lightweight composite receivers—the lower weighs only 5.5 oz., while the upper weighs 5.2 oz.—are impervious to water, solvents, heat and cold, offer very low coefficients of friction and conduct virtually zero heat, meaning they run cleaner, cooler and longer and can be fired more comfortably for longer periods of time. They contain 7071 hard-anodized aluminum reinforcing inserts around the fire control group, takedown pins and buffer tube mount, and the receiver halves are match fitted at the factory for zero action movement. The lower features a widely flared magazine well and integrally molded trigger guard and grasping grooves.

Every steel component has been coated with ROBAR’s NP3 for the maximum in corrosion resistance. composite receivers are molded from a special formula to ensure long-lasting durability.

Repeatedly dunked in between firing strings, the amphibian shrugged off our murky frog-pond water. Deadlines didn’t allow the same drill in saltwater.

Continuing the weatherproof theme, all internal components are NP3 Pus coated by ROBAR for high lubricity and 100% corrosion protection. NP3 Plus is a true composite coating, where sub micron particles of PTFE (Teflon) are co-deposited in the nickel matrix. As wear occurs, fresh particles of PTFE are exposed, maintaining the lubricating qualities of the coating.

The Amphibian is chambered in 5.56 NATO and is fitted with a light-profile 10.5-inch 416-R stainless steel barrel from Faxon Firearms, button rifled at a 1:8” twist rate. The threaded muzzle sports a 1.25-inch diameter KSP Flash Can muzzle brake that directs muzzle blast and report straight forward to protect the ears of both you and your fellow shooters. Both the barrel and Flash Can are also coated in NP3 Plus. The 10-inch, 1-piece, machined aluminum KSP Slim KeyMod handguard features a 22-slot Picatinny top rail, plus 8-slot KeyMod flats at the 3, 6 and 9 o’clock positions. Alignment of the composite upper receiver top rail with the aluminum handguard’s top rail was pretty good, but not perfect. The handguard top rail was about 1/64th inch lower than that of the upper receiver. The Kaiser US spec sheet says that the handguard is also NP3 Plus coated, but the handguard on our evaluation pistol was hard anodized in matte black. A low-profile NPR Plus coated gas block and stainless steel gas tube reside under the handguard, and a set of Magpul MBUS flip-up sights are fitted at the factory.

Controls are all standard AR fare. An ambi sling attachment point on the buffer tube and Magpul MBUS sights are standard. For testing we mounted an Aimpoint Micro T2 (Aimpoint.com) in an ADM (americandefensemfg.com) QD mount.

Furniture consists of a Magpul AFG angled foregrip mounted far forward on the 9 o’clock KeyMod flat and an XTECH ATG pistol grip that is adjustable for three different angles 17, 25 and 33 degrees) to ensure the proper fit for any hand. Surrounding the tail end of the NP3 Plus coated Mil-Spec buffer tube is a closed cell foam tube that provides a cushioned cheek rest for a 3-point hold. An ambidextrous, NP3 Plus coated sling attachment plate is mounted at the forward end of the buffer tube. Overall length is 26.5 inches and empty weight measured 5 lbs. 1 oz. without magazine, but with sights and furniture attached.

Furniture consists of a Magpul AFG angled foregrip mounted far forward on the 9 o’clock KeyMod flat and an XTECH ATG pistol grip that is adjustable for three different angles 17, 25 and 33 degrees) to ensure the proper fit for any hand. Surrounding the tail end of the NP3 Plus coated Mil-Spec buffer tube is a closed cell foam tube that provides a cushioned cheek rest for a 3-point hold. An ambidextrous, NP3 Plus coated sling attachment plate is mounted at the forward end of the buffer tube. Overall length is 26.5 inches and empty weight measured 5 lbs. 1 oz. without magazine, but with sights and furniture attached.

Except for being NP3 Plus coated, all of the controls are Mil-Spec fare and are found in their usual locations. The bolt is machined from Carpenter 158 steel, and it, along with the bolt carrier and other internals. are all NP3 Plus coated. The single stage Mil-Spec trigger is pretty typical of that genre. After a moderate degree of take-up and bit of stacking, it broke cleanly at an average pull weight of 5 lbs. 15 oz. The charging handle, which is also NP3 Plus coated, features and extended locking/pull latch mounted to its left-hand ear.

The Amphibian comes with a single-point sling, bright orange Brownell’s Safe Port empty chamber indicator and six Magpul PMAG Gen MA 30-round composite magazines, all packed in a Nanuk 940 protective case with PowerClaw latching system. Made from NK-7 impact-resistant resin, the Nanuk case is waterproof, Category 1 impact resistant and has a closed-cell foam interior with cutouts for the Amphibian, sling and six 30-round magazines.

For testing we mounted Aimpoint’s newest Micro—the T-2 red-dot sight ($761; aim point.com)—on the receiver top rail. The Micro T-2’s unlimited eye relief, 1X magnification and 2-MOA red dot made this the perfect sight for the close-range work the Amphibian was deigned for, but precise enough to reach out if need be. We sighted the Amphibian at 50-yards and went to work on our Salute steel-plate targets for the first 200-rounds to make sure it would run without fail. It did—even with a periodic dunking in the murky pond positioned smack dab in the middle of our shooting grounds. Why the water-boarding? Well, you can’t call a gun the “Amphibian” if it’s afraid to get wet, can you?

Sticking with our 50-yard sight-in distance, we moved to the bench to see if the Amphibian could match its perfect function with on-paper precision. Again, it did. Our best 5-shot group was punched with Black Hills 77-grain OTM 5.56x45mm ammunition, and measured an impressively-small 0.95 inches…outstanding performance for a pistol, without a doubt. All other groups came in below 2-inches, and the Amphibian showed a distinct preference for 62-grain and above ammunition.